JP2003224960A - Linear motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a linear motor which reduces the manufacture cost and the product cost. <P>SOLUTION: In the linear motor 1, which is equipped with a slender stator 2 and a tubular mover 2 set freely on the stator 2 so as to be free of shifting and where a plurality of magnets 20 for propulsion are arranged in its axial direction x on the side of the stator 2 and also armatures 30 are arranged on the side of the above mover 3 so as to oppose them, in the condition of specified space being opened to the magnets 20 for propulsion and besides which shifts the above mover 3 along the above stator 2, based on switching of the voltage to be applied to the armature 30, the space between the magnet 20 for propulsion and the above armature 30 is kept by bearings 40a and 40b for reciprocating motion. Hereby, the setup work becomes simple, and also an inexpensive material low in strength can be used for the stator, which can reduce the manufacture cost and the product cost. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is provided with an elongated stator and a tubular mover loosely fitted in the stator, and has an attractive force generated between an armature and a propulsion magnet. The present invention relates to a linear motor that uses a repulsive force to move a moving element.

[0002]

2. Description of the Related Art Conventionally, as a linear motor of this type,
2. Description of the Related Art There is known one provided with a substantially rod-shaped stator having a permanent magnet, and a cylindrical moving element having an armature and loosely fitted to the stator. In such a linear motor, the attraction force and the repulsive force are sequentially generated between the armature and the permanent magnet based on the switching of the voltage applied to the armature so that the mover moves along the stator. It was.

Further, in such a linear motor, by arranging permanent magnets and armatures radially (axisymmetrically) around the central axis of the stator, their balance (that is, a certain permanent magnet and an electric machine). The force that occurs between the child and
Balance of force generated between other permanent magnet and armature)
The gap between the armature and the permanent magnet was maintained at about 0.1 mm.

[0004]

However, in order to arrange the permanent magnets and the armature in the regular positions (positions of axial symmetry), careful assembly is performed using time and equipment so that the assembly error is reduced. However, there is a problem in that the manufacturing cost is increased. In addition, the strength must be ensured so that the stator or the like is not elastically deformed by the attractive force or repulsive force generated between the permanent magnet and the armature, and the use of expensive materials increases the product cost. There was a problem that it would end up. The present invention has been made in view of the above circumstances, and an object thereof is to provide a linear motor capable of reducing the manufacturing cost and the product cost.

[0005]

According to a first aspect of the present invention, an elongated stator (2) and a tubular mover (3) loosely fitted to the stator (2) so as to be movable. ) And,
A plurality of propulsion magnets (20) are arranged on the side of the stator (2) along the axial direction (x), and the propulsion magnets (2) are arranged.
0) with an armature (30) arranged on the side of the mover (3) so as to be opposed to the armature (30) with a predetermined gap, and by switching the voltage applied to the armature (30), In the linear motor (1) for moving the mover (3) along the stator (2), the propulsion magnet (2
0) and the armature (30) are reciprocating bearings (40a, 40b / 24a, 24b, ..., 50a, 5).
0b, ...).

According to a second aspect of the invention, the reciprocating motion bearings (40a, 40b) are rail portions (41a, 41b) arranged along the axial direction (x) of the stator (2).
And a sliding portion (43a, 43b) slidably arranged on the rail portion (41a, 41b), and these rail portion (41a, 41b) and sliding portion (43).
a, 43b) is arranged on the side of the stator (2) and the other is arranged on the side of the mover (3).

According to a third aspect of the invention, the propulsion magnet (2
0) is radially arranged around the central axis (CL) of the stator (2), the armature (30) is radially arranged so as to face each propulsion magnet (20), and ,
The reciprocating motion bearings (40a, 40b, ...) Are arranged radially around the central axis (CL) of the stator (2).

According to a fourth aspect of the present invention, the reciprocating motion bearings (24a, 24b, ..., 50a, 50b, ...) are rail portions arranged along the axial direction (x) of the stator (2). , And rollers (50a, 50b, ...) rotatably arranged on the rails, and these rails (24a, 24b, ...) And the rollers (50a). , 50b, ...) is arranged on the side of the stator (2) and the other is arranged on the side of the mover (3).

According to a fifth aspect of the present invention, the stator (2) has an elongated base portion (21), and the propulsion magnet (2).
0) are radially arranged on the outer peripheral surface of the base portion (21) around the central axis (CL) of the stator (2), and the rail portions (24a, 24b, ...) Are radially arranged. The magnet (2) is arranged between the propulsion magnet (20) and the propulsion magnet (20).
0) is fixed to the base portion (21), and the rollers (50a, 50b, ...) Are rotatably arranged on the side of the mover (3).

A sixth aspect of the present invention comprises an elongated stator (2), and a tubular mover (3) loosely fitted to the stator (2) so as to be movable. A plurality of propulsion magnets (20) are arranged along the axial direction (x) on the side of the stator (2), and the movement is performed so as to face the propulsion magnets (20) with a predetermined gap. The armature (30) is arranged on the side of the armature (3), and the armature (30)
In the linear motor (1) for moving the moving element (3) along the stator (2) by switching the voltage applied to the moving element (3), the side of the moving element (3) is arranged so that the same magnetic poles face each other. A magnet for holding the gap on the moving side (150
b, 150d, 150f), a stator side gap holding magnet (125) is placed on the side of the stator (2), and these gap holding magnets (150b and 1
25, 150d and 125, 150f and 125) by the repulsive force of the propulsion magnet (20) and the armature (30).
It is characterized in that the gap between and is properly maintained.

A seventh aspect of the present invention includes a stator (2) having an elongated shape and a tubular mover (3) loosely fitted to the stator (2) so as to be movable. A plurality of propulsion magnets (20) are arranged along the axial direction (x) on the side of the stator (2), and the movement is performed so as to face the propulsion magnets (20) with a predetermined gap. The armature (30) is arranged on the side of the armature (3), and the armature (30)
In a linear motor (1) that moves the mover (3) along the stator (2) by switching the voltage applied to the mover, the mover (3) is moved to the mover (3) side so as to face each other. Child side gap maintaining magnet (150b,
150d, 150f) and a stator side gap holding magnet (125) on the side of the stator (2), and the mover side gap holding magnet (150b, 150).
d, 150f) and the stator side gap maintaining magnet (12
One of 5) is an electromagnet and the other is a permanent magnet,
At least one gap detecting means for detecting a gap between the propulsion magnet (20) and the armature (30) is arranged, and the electromagnet is turned on / off according to a signal from the gap detecting means. Accordingly, the gap between the propulsion magnet (20) and the armature (30) is appropriately maintained.

According to the invention of claim 8, the propulsion magnet (2
0) are radially arranged around the central axis (CL) of the stator (2), and the armature (30) is radially arranged so as to face each propulsion magnet (20). The stator-side gap maintaining magnet (125) is at a position where it does not overlap with the propulsion magnet (20), and is the stator (2).
A plurality of them are arranged radially around the central axis (CL).

[0013]

According to the invention of claim 1, the gap between the propulsion magnet (20) and the armature (30) has a reciprocating motion bearing (40a, 40b / 24a, 24b, ..., 50).
a, 50b, ...), the smooth movement of the linear motor (1) can be ensured. Also,
As in the case of the conventional device, the assembly error does not have to be made smaller than necessary when assembling the stator and the like, and the number of assembly work steps can be reduced. Further, the elastic deformation of the stator (2) caused by the attractive force or repulsive force between the propulsion magnet (20) and the armature (30) causes the reciprocating motion bearings (40a, 40b / 24a, 24b). ,,, 5
0a, 50b, ...), it is not necessary to increase the strength of the stator more than necessary, so that the weight can be reduced and the product cost can be reduced accordingly.

According to the invention of claim 2, the rail portion (41
Since the existing reciprocating motion bearing, which is composed of a, 41b) and the sliding parts (43a, 43b), can be reused, the product cost can be reduced.

According to the invention of claim 3, the propulsion magnet (2
0) is a linear motor having a plurality of radial arrangements around the central axis (CL) of the stator (2), the reciprocating bearings (40a, 40b, ...) Properly adjust the gap. Therefore, the smooth movement of the linear motor (1) can be secured.

According to the fourth aspect of the present invention, the reciprocating motion bearing includes rail portions (24a, 24b, ...) And rollers (5).
0a, 50b, ...), the weight of the device can be reduced.

According to the invention of claim 5, the propulsion magnet (2
0) is a linear motor having a structure in which a plurality of radial arrangements are provided around the central axis (CL) of the stator (2), the gap can be properly maintained and the linear motor (1) can be smoothly moved. Can be secured.

According to the sixth aspect of the present invention, the smooth movement of the linear motor (1) can be ensured as in the above-mentioned respective aspects of the invention, and the moving element side gap holding magnets (150b, 150d, 150f) are also provided. Since it is a non-contact type that utilizes the repulsive force between the magnet and the stator side gap holding magnet (125), it is possible to avoid wear between members and generation of sliding noise.

According to the invention of claim 7, not only the same effect as that of the invention of claim 6 is obtained, but also by turning on / off the electromagnet, the propulsion magnet (20) and the armature (30). The gap between and can be maintained more appropriately.

According to the invention of claim 8, the propulsion magnet (2
0) is a linear motor having a structure in which a plurality of radial arrangements are provided around the central axis (CL) of the stator (2), the gap can be properly maintained and the linear motor (1) can be smoothly moved. Can be secured.

The numbers in parentheses are for convenience of showing the corresponding elements in the drawings, and the present description is not limited to the description in the drawings.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

First, the overall structure of the linear motor according to the present invention will be described with reference to FIGS. Here, FIG. 1 is a perspective view showing an appearance of a linear motor according to the present invention, FIG. 2 is a perspective view showing an internal structure of the linear motor, and FIG. 3 is a perspective view showing a linear motor according to the present invention. FIG. 4 is a vertical sectional view showing the structure, and FIG. 4 is a horizontal sectional view showing the structure of the linear motor according to the present invention.

As shown in FIGS. 1 to 3, a linear motor 1 according to the present invention has an elongated (substantially rod-shaped) stator 2.
And a tubular mover 3 that is loosely fitted to the stator 2 so as to be movable. The stator 2 has a permanent magnet (propulsion magnet) 20 along the axial direction x.
Are arranged, and an armature 30 is arranged on the other moving element 3 so as to face the permanent magnet 20 in a state where a predetermined gap is opened, and moves based on switching the voltage applied to the armature 30. The child 3 is configured to move along the stator 2.

Here, the detailed structure of the stator 2 is shown in FIG.
~ It demonstrates along FIG. 5 is a perspective view showing the outer appearance of the stator, FIG. 6 is a perspective view showing the outer appearance of the base portion, and FIG. 7 is an exploded perspective view for explaining the mounting state of the fixing bar and the like. Yes, FIG. 8 is a schematic diagram for explaining the arrangement position of the permanent magnets.

The stator 2 is provided with a base portion 21 having an elongated cylindrical shape as shown in FIGS. This base 2
1, the outer peripheral surface of which is composed of six flat surface portions 210a, 210b, ... And which has a substantially hexagonal external appearance (the portion is shown in FIG.
, A plurality of them are arranged along the axial direction x as shown by the symbols A ₁₁ , A ₁₂ , A ₁₃ , ..., However, if it is not necessary to distinguish them, simply add the symbol “A ₁ ”. Will be explained. Since this portion is a portion for mounting the magnet 20 as described below, it will be hereinafter referred to as a "magnet mounting portion", and a portion A ₂ having a substantially cylindrical appearance (hereinafter, referred to as "annular shape"). And a portion A ₂ ″) are alternately arranged.

The plane portions 210a, 210b, ...
To the permanent magnets 20 (if it is necessary to distinguish between the permanent magnets mounted on the respective flat surface portions 210a, 210b, ..., The reference numerals 20a, 20b, ... Are used to distinguish them. Are simply assigned the reference numeral 20). As a result, the permanent magnets 20 are arranged in the radial direction around the central axis CL of the stator 2 in one magnet mounting portion A ₁ (see FIG. 4), and in the axial direction x of the stator 2. Are arranged at a constant pitch (see FIGS. 1 to 3, etc.).

The magnet 20 includes flat portions 210a, 21
0b, ... are mounted on the flat surface portions 210a, 210
b, ... A flat surface having substantially the same size (reference numeral 200 in FIG. 6).
reference. Hereinafter, the surface is referred to as "mounting surface", and the opposite side (see reference numeral 201; hereinafter referred to as "outer peripheral surface") is configured to represent a part of the cylindrical outer peripheral surface. In addition, each magnet 20 is magnetized so that the mounted surface 200 and the outer peripheral surface 201 have different magnetic poles. The magnetic poles on the outer peripheral surface 201 of the six permanent magnets 20a, 20b, ... Arranged in _one magnet mounting portion A ₁ are all the same, and the magnetic poles on the outer peripheral surface 201 are S in the axial direction x. It is set so as to be switched alternately such as -N-S-N-S-N. That is, the stator 2 shown in FIG.
In the magnet mounting portion indicated by reference numeral A ₁₁ , the outer peripheral surface 201
Pole are all S poles, the outer peripheral surface 201 in the magnet mounting portion shown in-code _{A 12}
Pole are all N poles, the outer peripheral surface 201 in the magnet mounting portion shown in-code _{A 13}
Pole are all S poles, the outer peripheral surface 201 in the magnet mounting portion shown in-code _{A 14}
The magnetic poles of are all N poles, and are configured so as to ... By arranging the permanent magnets 20 in this way, the magnets adjacent to each other in the axial direction x attract each other, which makes it easy to attach the magnets 20 to the base 21 and facilitate the assembly work of the stator 2. Produce an effect.

By the way, one magnet mounting portion A₁At
Three planar portions 210a, 210b, which are circumferentially adjacent to each other,
210c (and each plane part 210a, 210b, 210c
Magnets 20a, 20b, 20c respectively attached to
Is a constant pitch p in the axial direction x, as shown in detail in FIG.₁
They are arranged so that they are displaced from each other, and the remaining three plane portions 2
10d, 210e, 210f (and each flat part 210d,
Magnets 20d attached to 210e and 210f,
20e, 20f) also has a constant pitch p in the axial direction x. ₁One by one
It is arranged as follows. Furthermore, the central axis of the stator 2
Two flats arranged at an angle of 180 degrees around CL
Surface portion (flat surface portion 210a and flat surface portion 210d, flat surface portion 210
b and the plane portion 210e, the plane portion 210c and the plane portion 210
f) should not be displaced in the axial direction x (ie
They are arranged so that the positions in the direction x coincide with each other.

By the way, in the above-mentioned annular portion A ₂ , as shown in FIGS. 5, 7 and 8, the spacer 2 is arranged so as to fill the gap between the magnets 20 arranged in the axial direction x.
2 are arranged (such spacers are provided between the magnets 20a and 20a, between the magnets 20b and 20b, between the magnets 20c and 20c, between the magnets 20d and 20d).
, And between the magnets 20e and 20e, and between the magnets 20f and 20f, but if it is necessary to distinguish them, reference numerals 22a, 22b,
..., and the reference numeral 22 is simply attached when there is no need for distinction).

That is, in the axial direction x of the stator 2, as shown in FIGS. 5 and 7, the permanent magnets 20 and the spacers 22 are alternately arranged.
The end faces (end faces in the circumferential direction) of the spacers 22 and the spacers 22 form a slender substantially flat surface portion along the axial direction x, and the end faces facing each other (for example, the end faces in the circumferential direction of the permanent magnet 20a and the spacer 22a and the permanent magnet). 20b and the end face of the spacer 22b in the circumferential direction)
A groove (see reference numeral 23 in FIG. 7) is formed between the two. The groove portion 23 has a cross-sectional shape with a narrow inner peripheral side and a wide outer peripheral side, and six radial grooves are formed on the outer peripheral surface of the base portion 21. A fixed bar 24 having a wedge-shaped cross section having a narrow inner peripheral side and a wide outer peripheral side is attached to these groove portions 23 with screws. Since the groove portion 23 and the fixing bar 24 have the above-described cross-sectional shape, the fixing bar 24 mounted in the groove portion 23 holds both end surfaces (both circumferential end surfaces) of the permanent magnet 20 and the spacer 22 against the base portion 21. Attach and play a role of fixing them.

By the way, FIG. 9 is a cross-sectional view showing the structure of the stator 2. Reference numeral 24a, 24b, 24 in FIG.
As indicated by c, 24d, 24e, and 24f, the six fixing bars are arranged radially. Of these, 18
A pair of solid bars 24c, 24 placed on opposite sides by 0 degrees
A rail portion of an LM guide (reciprocating motion bearing) is attached to f so as to extend along the axial direction x of the stator 2 (details will be described later).

Next, the structure of the mover 3 will be described with reference to FIGS.
Etc. will be described. Here, FIG. 10 is an exploded perspective view showing the structure of the mover 3, FIG. 11 is a perspective view showing the structure of the mover 3, and FIG. 12 is a perspective view showing the detailed shape of the armature. Yes, FIG. 13 is an exploded perspective view for explaining an assembled state of the armature. 14 is a cross-sectional view showing another example of the method of regulating the gap between the permanent magnet 20 and the armature 30, FIG. 15 is a perspective view showing the method of supporting the roller, and FIG. FIG. 17 is a cross-sectional view showing another example of the gap regulating method between the permanent magnet 20 and the armature 30, and FIG. 17 is another example of the gap regulating method between the permanent magnet 20 and the armature 30. FIG.

The mover 3 has six iron core members 31 as shown in FIG. 4, and these six iron core members 31 are the six magnet rows 20a, ..., 20b ,.
, 20d, ..., 20e, ..., 20f ,. As shown in FIGS. 3 and 10, each iron core member 31 is planted in a portion (hereinafter referred to as “back portion”) 311 arranged along the axial direction x and from the back portion 311 toward the central axis CL. The plurality of iron core portions 310 are formed in a comb tooth shape. Then, each iron core portion 310
11, a coil 32 is wound around as shown in FIG. 11, and the iron core portion 310 and the coil 32 constitute an armature 30 (that is, the armature 30 is
Each permanent magnet 20a, 20b, 20c, 20d, 20e,
It will be arranged radially around the central axis CL so as to face 20f). In addition, in FIG. 10 and FIG.
Only one of the six iron core members 31 is shown. Also,
FIG. 10 shows only one coil 32, and FIG.
Only one armature 30 is shown.

By the way, as shown in detail in FIGS. 12 and 13, the coil 32 has a box shape having a hollow portion 32a, and the armature 30 is configured by being fitted into the iron core portion 310. It is like this. A projection 310a is formed at the tip of the iron core 310 to prevent the coil 32 from coming off easily. In the present embodiment, the core portion 31 of the coil 32
Since the attachment to 0 is performed by using the protrusion 310a as described above, unlike the case where an adhesive is used, labor such as drying is not required and the attachment work can be simplified. It is possible to reduce the assembly error.

The moving element 3 according to the present invention is shown in FIG.
As shown in FIG. 3, a plurality of annular members 33 having the shape detailed in FIG. Six groove portions (hereinafter referred to as “outer groove portions”) 330 are formed on the outer peripheral side of the annular member 33 at equal intervals, and each outer groove portion 330 has an iron core member as shown in FIGS. 10 to 13. The back part 311 of 31 is fitted from the outside (from the outside of the annular member 33). Then, the outer surface of the back portion 311 and the outer surface 33a of the annular member 33 are configured to present cylindrical surfaces having substantially the same curvature as shown in FIG. In addition, as shown in FIG.
The annular member 33 is always arranged between the core 10 and the iron core portion 310, but only one annular member 33 is shown in FIGS. 10 and 11 for easy understanding. According to the present embodiment, since the iron core member 31 is attached to the annular member 33 by using the outer groove portion 330 as described above, the positional deviation in the circumferential direction (the circumferential direction of the annular member 33) is minimized. As a result, they can be accurately arranged radially as shown in FIG. Further, since the adhesive is not used for attaching the iron core member 31 to the annular member 33, the labor of drying or the like is not required, the attaching work can be simplified, and the assembling error can be reduced. Furthermore, the mover 3 in the present invention is provided with the case 34 as shown in FIGS. 3 and 4, and the iron core member 31, the annular member 33, and the like described above are housed in the case 34. Members 31, 3
Since the outer shape of 3 is the same in any cross section, the iron core member 31, the annular member 33, and the like are assembled and then inserted into the case 34 to complete the assembly, and the assembly work is easy. Has the effect.

Further, on the inner peripheral side of the annular member 33,
As shown in FIG. 10, groove portions (hereinafter, referred to as “inner groove portions”) 331 are formed at positions corresponding to the outer groove portions 330, and the inner groove portions 331 are described in detail in FIGS. 12 and 13. As described above, the coil 32 is adapted to be fitted therein, and thus the coil 32 can be positioned. Further, since no adhesive is used between the coil 32 and the annular member 33, the labor for drying or the like is not required, the mounting work can be simplified, and the assembly error can be reduced. Furthermore, since the coil 32 is in contact with the annular member 33 and is fitted into the iron core portion 310 by the protrusion 310a, the annular member 33 can be prevented from coming off from the iron core member 31. Therefore, there is an effect that the assembling work of the mover 3 becomes easy.

By the way, as shown in FIG. 1, in the moving element 3, blocks 42a and 42b of the LM guide are arranged at positions facing the stator side rails 41a and 41b. The rail 4 is attached to the blocks 42a and 42b.
LM nut (that is,
Reciprocating bearing sliding parts) 43a, 43b are attached to these rails 41a, 41b, block 4
2a, 42b and LM nuts 43a, 43b
M guides 40a and 40b are configured. According to the present embodiment, although iron core portion 310 is extended toward stator-side permanent magnet 20 and attracted to permanent magnet 20 with a large force, iron core member 31 is supported by annular member 33 as described above. In addition, since the LM guides 40a and 40b are interposed between the stator 2 and the mover 3, the iron core portion 31
It is possible to properly maintain the gap between 0 and the permanent magnet 20 (that is, the gap between the permanent magnet 20 that is the propulsion magnet and the armature 30). In the linear motor shown in the figure, the rails 41a and 41b are arranged on the side of the stator 2, and the blocks 42a and 42b and the LM nuts 43a and 4b.
3b is arranged on the side of the mover 3, but it is not limited to this, of course, the rails 41a, 41b are arranged on the side of the mover 3, and the blocks 42a, 42b and the LM nuts 43a, 43b are the stators. It may be arranged on the second side. Further, the linear motor shown in the figure uses only two LM guides, but of course the number is not limited to this, and three or more LM guides may be radially arranged around the central axis CL of the stator 2. Is also good.

The linear motor 1 according to the present embodiment
In the above, the armatures 30 arranged in one row in the axial direction x are arranged in six rows radially around the central axis CL, but between each armature row and each armature row. In this case, a void portion will be formed as indicated by reference numeral S in FIG. The void S is formed along the axial direction x and has open both ends, and air moves in and out of the void S as the mover 3 moves in the direction x, so that the armature 30 Are configured to be cooled.

In this embodiment, six magnets 20 are arranged with respect to the cross section of the stator 2, but an even number may be used, and eight or ten may be used. Regardless of the number of such magnets, two magnets 180 degrees apart (in the present embodiment, permanent magnet 20a and permanent magnet 20d, permanent magnet 20b and permanent magnet 20e, permanent magnet 20c and permanent magnet 20f) Of the magnets (in the present embodiment, the permanent magnet 20a and the permanent magnet 20b, the permanent magnet 20b and the permanent magnet 20c) that are aligned in the axial direction x and are adjacent to each other in the circumferential direction. It is advisable to shift by a constant pitch p ₁ .

According to the present embodiment, each magnet row (ie, the magnet row composed of one row of permanent magnets 20 arranged in the x-axis direction) is composed of a plurality of permanent magnets 20. It is easy to align the direction of the magnetic flux of each permanent magnet 20 in the direction perpendicular to the mounting surface, and it is possible to form a uniform magnet array without disturbance in the direction of the magnetic flux.

By the way, in the above-described embodiment, the base 2
Although 1 is integrally formed of one member, it may be formed separately in the axial direction or the circumferential direction. Alternatively, only the permanent magnets may be arranged in a cylindrical shape without using the base portion 21.

Further, although the stator 2, the base 21 and the magnet 20 are cylindrical in the above-mentioned embodiments, the present invention is not limited to this, and may be polygonal. Further, although the stator 2 (specifically, the base portion 21) has a hollow cylindrical shape, it may have a solid rod shape.

By the way, in the above-described embodiment, the LM guides 40a and 40b are used to regulate the gap between the permanent magnet 20 and the armature 30, but other methods may be used.

For example, on the side of the stator 2, as shown in FIG. 14 (b), permanent magnets 20a, which are radially arranged,
The fixed bars (rail portions) 24a, 24b, ... are radially arranged between the 20b, ... and along the axial direction x, and the movable bar 3 has a rotatable roller as shown in FIG. These rollers 50 are provided with 50a, 50b, ...
.. can be rolled on the surfaces of the fixed bars 24a, 24b, ... (See FIG. 14 (a)). In this case, the fixed bars 24a, 24
.. and the rollers 50a, 50b, .. 15, reference numeral 51 indicates a plate for supporting the rollers 50a, 50b, ..., And reference numerals 52a, 52b, ... Represent the rotation axes of the rollers 50a, 50b ,. Here, FIG.
Also, although the number of rollers is six in FIG. 15, it is not limited to this and may be three (FIG. 16).
reference). Also, in these figures, the fixed bar (rail section)
24a, 24b, ... Are arranged on the side of the stator 2 and rollers 50a, 50b, ... are arranged on the side of the mover 3, but of course the invention is not limited to this.
The elements corresponding to 4a, 24b, ... May be arranged on the side of the moving element 3 and the elements corresponding to rollers 50a, 50b ,.

Further, as another method, a method of using a magnet for maintaining a gap can be mentioned. For example, FIG. 17 (a)
As shown in FIG. 6, the six fixing bars 124a, 124b, ...
Are arranged radially, and three fixed bars 124 in them are arranged.
Magnets (stator-side gap maintaining magnets) 125 are arranged along the axial direction at b, 124d, and 124f. That is,
The magnets 125 are radially arranged around the center axis CL of the stator 2 at a position where they do not overlap the permanent magnets 20. The magnets 125 are provided on the side of the moving element 3.
(Mover-side gap holding magnet) 15 so as to face
0b, 150d, and 150f may be arranged, and the magnetic poles on the opposite side may be the same pole so that a repulsive force is generated between the magnets. Then, due to the repulsive force of these gap holding magnets, the gap between the permanent magnet 20 and the armature 30 is properly maintained. In addition,
Magnets (movement-side gap holding magnets) 150b, 150d,
150f may be arranged at the positions of the fixed bars 124b, 124d, and 124f (that is, between the armature rows), but L shown by reference numerals 40a and 40b in FIG.
Like the M guide, at least three radially (that is, at least three are arranged on the front side and at least three are arranged on the rear side) at a position projecting in the axial direction from the six armature rows. , A total of at least 6 will be arranged).

As described above, the magnet (stator side gap maintaining magnet) 125 and the magnet (movement side gap maintaining magnet) 150.
Although b, 150d and 150f are arranged, at least one of the magnets facing each other is an electromagnet and the other is a permanent magnet, and at least one gap detecting means for detecting a gap between the permanent magnet 20 and the armature 30 is provided. (Or as many permanent magnet rows as there are rows of permanent magnets 20 arranged in the x-axis direction) are provided, and the electromagnets are turned on / off according to a signal from the gap detecting means to turn the permanent magnets 20 and the armature. Three
The gap with 0 may be maintained properly. In this case, the gap holding magnets on the mover side may be respectively arranged between the armature rows and the armature rows, but in FIG.
Like the LM guides indicated by 0a and 40b, at least three radially (that is, at least three are arranged on the front side and at least three on the rear side) at a position projecting in the axial direction from the six armature rows. Therefore, it is preferable to arrange at least 6 in total.

In addition to the permanent magnet (propulsion magnet) 20, a stator-side gap maintaining magnet is not provided, but the permanent magnet 20 is made to serve both as a propulsion magnet and a stator-side gap maintaining magnet. You can In that case, at least three radial magnets (electromagnets) for holding the moving element side are arranged at positions axially protruding from the six armature rows, as in the LM guides indicated by reference numerals 40a and 40b in FIG. (That is, at least three are arranged on the front side and at least three are arranged on the rear side, so a total of at least six will be arranged before and after). In such a case, the surface magnet of the permanent magnet facing the magnet for holding the gap on the mover side is switched to S → N → S → N with the movement of the mover, but the gap on the mover side is kept in synchronization with it. The gap can be maintained by switching the magnetic poles of the working magnet. With such a configuration, the stator side gap maintaining magnet and the propulsion magnet can be used in common, so that the number of parts can be reduced and the cost can be reduced.

Next, the operation of this embodiment will be described.

Now, when a voltage is sequentially applied to the coil 32 at a predetermined timing to excite the armature 30, an attractive force or a repulsive force acts between each armature 30 and each permanent magnet 20, The mover 3 is moved in the axial direction x of the stator 2.

[Brief description of drawings]

FIG. 1 is a perspective view showing an appearance of a linear motor according to the present invention.

FIG. 2 is a perspective view showing an internal structure of the linear motor.

FIG. 3 is a vertical cross-sectional view showing the structure of a linear motor according to the present invention.

FIG. 4 is a cross-sectional view showing the structure of the linear motor according to the present invention.

FIG. 5 is a perspective view showing an appearance of a stator.

FIG. 6 is a perspective view showing an appearance of a base portion.

FIG. 7 is an exploded perspective view for explaining a mounting state and the like of a fixed bar.

FIG. 8 is a schematic diagram for explaining an arrangement position of permanent magnets.

FIG. 9 is a cross-sectional view showing the structure of the stator 2.

FIG. 10 is an exploded perspective view showing a structure of a mover 3.

FIG. 11 is a perspective view showing a structure of a mover 3.

FIG. 12 is a perspective view showing a detailed shape of an armature.

FIG. 13 is an exploded perspective view for explaining an assembled state of the armature.

FIG. 14 is a cross-sectional view showing another example of the method of regulating the gap between the permanent magnet 20 and the armature 30.

FIG. 15 is a perspective view showing a method of supporting a roller.

FIG. 16 is a cross-sectional view showing another example of the method of regulating the gap between the permanent magnet 20 and the armature 30.

FIG. 17 is a transverse cross-sectional view showing another example of the gap regulating method between the permanent magnet 20 and the armature 30.

[Explanation of symbols]

1 …………………… Linear motor 2 …………………… Stator 3 …………………… Motor 20 ……………… Permanent magnet (propulsion magnet) 21 ……………… ... Base parts 24a, 24b ... Fixed bars (rail parts) 40a, 40b ... LM guides (bearings for reciprocating motion) 41a, 41b ... Rail parts 43a, 43b ... LM nuts (sliding parts) 50a, 50b, ... Rollers 125 ... ............ Stator-side gap maintaining magnets 150b, 150d, 150f ... Translator-side gap maintaining magnet p ₁ …… Displacement (pitch) CL …… Central axis

Claims (8)

[Claims] 1. An elongated stator, and a tubular mover that is loosely fitted to the stator so as to be movable,
A plurality of propulsion magnets are arranged along the axial direction on the side of the stator, and an armature is arranged on the side of the mover so as to face the propulsion magnets with a predetermined gap therebetween, and In a linear motor that moves the mover along the stator by switching the voltage applied to the armature, the gap between the propulsion magnet and the armature is held by a reciprocating bearing. A linear motor characterized in that 2. The reciprocating motion bearing comprises a rail portion arranged along the axial direction of the stator and a sliding portion slidably arranged on the rail portion, and these. 2. The linear motor according to claim 1, wherein one of the rail portion and the sliding portion is disposed on the side of the stator, and the other is disposed on the side of the moving element. 3. A plurality of the propulsion magnets are radially arranged around a central axis of the stator, the armature is radially arranged so as to face each propulsion magnet, and the reciprocating motion is performed. The linear motor according to claim 1 or 2, wherein the bearings are radially arranged around a central axis of the stator. 4. The reciprocating bearing includes a rail portion arranged along the axial direction of the stator and a roller rotatably arranged on the rail portion, and these rails are also provided. The linear motor according to claim 1, wherein one of the section and the roller is arranged on the side of the stator, and the other is arranged on the side of the mover. 5. The stator has an elongated base portion, a plurality of the propulsion magnets are radially arranged around a central axis of the stator on the outer peripheral surface of the base portion, and the rail portions are The magnets are arranged between the propulsion magnets and the propulsion magnets that are radially arranged, the magnets are fixed to the base portion, and the rollers are rotatably arranged on the mover side. The linear motor according to claim 4, wherein the linear motor is provided. 6. An elongated stator, and a cylindrical mover that is loosely fitted to the stator so as to be movable,
A plurality of propulsion magnets are arranged along the axial direction on the side of the stator, and an armature is arranged on the side of the mover so as to face the propulsion magnets with a predetermined gap therebetween, and In a linear motor that moves the mover along the stator based on switching the voltage applied to the armature, a mover-side gap holding magnet is provided on the mover side so that the same magnetic poles face each other. The stator side gap holding magnets are arranged on the side of the stator, and the gap between the propulsion magnets and the armature is properly maintained by the repulsive force of these gap holding magnets. A linear motor characterized by dripping. 7. An elongated stator, and a tubular mover that is loosely fitted to the stator so as to be movable,
A plurality of propulsion magnets are arranged along the axial direction on the side of the stator, and an armature is arranged on the side of the mover so as to face the propulsion magnets with a predetermined gap therebetween, and In a linear motor that moves the mover along the stator based on switching the voltage applied to the armature, mover-side gap holding magnets are arranged on the mover side so as to face each other. A stator side gap maintaining magnet is arranged on the side of the stator together with one of the moving element side gap maintaining magnet and the stator side gap maintaining magnet, and the other is a permanent magnet. At least one gap detecting means for detecting a gap between the propulsion magnet and the armature is arranged, and the electromagnet is turned on / off according to a signal from the gap detecting means.
A linear motor characterized in that a gap between the propulsion magnet and the armature is appropriately maintained based on being turned off. 8. A plurality of the propulsion magnets are radially arranged around a central axis of the stator, the armature is radially arranged so as to face each propulsion magnet, and the stator-side gap holding member is provided. 8. The magnet for use is arranged at a position where it does not overlap the magnet for propulsion and is radially arranged around the central axis of the stator.
Linear motor described in.